I am supposed to set up a simple PayPal button for a client's site. This should direct to the PayPal page with a description and the amount to pay on it. People then login or pay by credit card etc. (haven't done this much before)

Do I need access to the client's PayPal account to do this? The client says that they don't want to give me access. Fair enough...

But doesn't PayPal have any feature for such cases, e.g. web designer/developers access to an account?